A Brief Review of a Common Clinical Question: Intravenous Diltiazem or Metoprolol for Atrial Fibrillation with Rapid Ventricular Response?

Two classes of rate controlling medications—beta blockers (BBs) and non- dihydropyridine calcium channel blockers (CCBs)—are given to patients who present with atrial fibrillation (AF) with rapid ventricular response (RVR). Both are Class I recommendations from the American Heart Association (AHA), American College of Cardiology (ACC), and Heart Rhythm Society (HRS) for the management of AF with RVR. Multiple studies support the view that diltiazem is more effective than metoprolol, even though data from the AFFIRM trial suggests BBs are more frequently used. CCBs are generally avoided in AF with RVR patients who have concomitant heart failure with reduced ejection fraction (HFrEF) for concern of triggering decompensation. However, some recent studies indicate this idea may be unfounded. The aim of this article is to compare the efficacy of diltiazem and metoprolol for rate control in AF with RVR and examine the use of diltiazem in patients with both AF with RVR and HFrEF.